Chronic obstructive pulmonary disease specific agents

Nonselective beta blockers affect beta-2 receptors on the lungs as well as beta-1 receptors on the heart, and these nonselective agents can increase bronchocon-striction in patients with asthma and chronic obstructive pulmonary disease. Hence, a drug that is more specific for beta-1 receptors is preferred in these patients. Beta blockers can also produce excessive slowing of cardiac conduction in some patients, resulting in an increase in arrhythmias. Severe adverse reactions are rare, however, and beta blockers are well-tolerated by most patients when used appropriately to treat arrhythmias. 

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